Transcript Computers
Computers Hardware Acknowledgments Thanks to the following web site and people for the materials and images used in this presentation: -Wikipedia -Prof. Patrice Koehl -Sean Davis -Nick Puketza -http://microsoft.toddverbeek.com -http://www.webopedia.com -http://www.engin.umd.umich.edu/ -http://www.dell.com -http://www.intel.com -http://www.apple.com -http://www.ibm.com -http://homepages.feis.herts.ac.uk/~msc_ice/unit2/ -http://www.howstuffworks.com Computer Layers Hardware BIOS Operating System Applications Computer Layers Hardware BIOS Operating System Applications Computers What different types of computers are there? Computers Laptop, desktop, workstation, Tablet PC, netbooks, chromebook, etc. Mainframe Supercomputer Server farm and data center (cloud computing) Looking inside a computer… Computers come in different shapes and sizes, from small laptops (notebooks), desktops to mainframe computers. They all share however the same internal architecture! IBM Blue Gene Supercomputer Data Center Computer: basic scheme Input devices Output devices CPU Storage The motherboard: backbone of the computer Power supply connector Slot for memory: RAM Hard drive connectors Slot for CPU Input/Output: Keyboard, Mouse,… Extension cards: Video, sound, internet… Hardware communication: buses (33 to 1333 MHz) (66 MHz) (33 to 1333 MHz) ISA devices ISA bus (8.3 MHz) CPU (33 or 66 MHz) (up to 300 MHz) Cache Backside bus (speed of processor) Hardware communication: buses The memory bus: a 16 bit bus Communication between the CPU and the RAM is defined by: CPU RAM -the CPU speed -The RAM speed -The number of bits transferred per cycle Other buses: USB, Firewire, PCI Express,… CPU The Central Process Unit (CPU): The “brain” of the computer CPUs are getting smaller, and can include more than one “core” (or processors). CPUs get hot, as their internal components dissipate heat:it is important to add a heat sink and fans to keep them cool. CPU Transistors The integrated circuit (IC) allowed a large number of transistors to be manufactured on a single semiconductor-based die, or "chip." VLSI (very large scale IC) Also known as microprocessor, microcontroller, etc. It starts from the beach.... 800x magnification of an early chip Moore’s Law The empirical observation that the transistor density of integrated circuits, with respect to minimum component cost, doubles every 24 months. attributed to Gordon E. Moore, a co-founder of Intel. Doubling is very powerful. A few numbers Name Date Transistors Microns Clock speed Data width MIPS 8080 1974 6,000 6 2 MHz 8 bits 0.64 8088 1979 29,000 3 5 MHz 16 bits 8-bit bus 0.33 80286 1982 134,000 1.5 6 MHz 16 bits 1 80386 1985 275,000 1.5 16 MHz 32 bits 5 80486 1989 1,200,000 1 25 MHz 32 bits 20 Pentium 1993 3,100,000 0.8 60 MHz 32 bits 64-bit bus 100 Pentium II 1997 7,500,000 0.35 233 MHz 32 bits 64-bit bus ~300 Pentium III 1999 9,500,000 0.25 450 MHz 32 bits 64-bit bus ~510 Pentium 4 2000 42,000,000 0.18 1.5 GHz 32 bits 64-bit bus ~1,700 Pentium 4 "Prescott" 2004 125,000,000 0.09 3.6 GHz 32 bits 64-bit bus ~7,000 CPU speed 1 hertz = 1 "cycle" per second A typical watch operates at 1 Hertz (one "clock tick" per second) Intel Pentium D: 3.20 GigaHertz (GHZ) 3.2 billion cycles per second CPU ALU (Arithmetic logic unit) Control Unit Register Cache Connected to memory through North Bridge. Instructions are stored in machine language as binary number. The Fetch/Execute Cycle A machine cycles through a series of operations, performing an instruction on each round Fetch/execute cycle is a five-step cycle: 1. Instruction Fetch (IF) 2. Instruction Decode (ID) 3. Data Fetch (DF) 4. Instruction Execution (EX) 5. Result Return (RR) Acknowledgement: Lawrence Snyder, “fluency with information technology”, for following slides Control Unit Hardware implementation of the Fetch/Execute Cycle Its circuitry fetches an instruction from memory and performs other operations of the cycle on it A typical instruction might have the form ADD 2000, 2080, 4000 This instruction asks that the numbers stored in locations 2000 and 2080 be added together, and the result stored in location 4000 Data Fetch step must get these two values and after they are added, Result Return step will store the answer in location 4000 Instruction Interpretation Process of executing a program Computer is interpreting our commands, but in its own language Before the F/E Cycle begins, some of the memory locations and the PC are visible in the control unit Instruction Interpretation (cont'd) Execution begins by moving instruction at the address given by the PC from memory to control unit Instruction Interpretation (cont'd) Bits of instruction are placed into the decoder circuit of the CU Once instruction is fetched, the PC can be readied for fetching the next instruction Instruction Interpretation (cont'd) In Instruction Decode step, ALU is set up for the operation Decoder will find the memory address of the instruction's data (source operands) Most instructions operate on two data values stored in memory (like ADD), so most instructions have addresses for two source operands These addresses are passed to the circuit that fetches them from memory during the next step, Data Fetch Decoder finds destination address for the Result Return step, and places it in RR circuit Decoder determines what operation the ALU will perform, and sets it up appropriately Instruction Execution Instruction Execution: The actual computation is performed. For ADD instruction, the addition circuit adds the two source operands together to produce their sum Instruction Result Return: result of execution is returned to the memory location specified by the destination address. Once the result is returned, the cycle begins again. Many, Many Simple Operations Computers can only perform about 100 different instructions About 20 different kinds of operations (different instructions are needed for adding bytes, words, decimal numbers, etc.) Everything computers do must be reduced to some combination of these primitive, hardwired instructions Examples of Other Instructions Besides ADD, MULT (multiply) and DIV (divide), other instructions include: Shift the bits of a word to the left or right, filling the emptied places with zeros and throwing away bits that fall off the end Compute logical AND (test if pairs of bits are both true, and logical OR, which tests if at least one of two bits is true Test if a bit is zero or non-zero, and jump to new set of instructions based on outcome Move information around in memory Sense signals from input/output devices CISC vs. RISC Cycling the F/E Cycle Computers get their impressive capabilities by executing many of these simple instructions per second The Computer Clock: Determines rate of F/E Cycle Measured in megahertz, or millions of cycles per second CPU: Instruction Execution Engines What computers can do Deterministically perform or execute instructions to process information The computer must have instructions to follow What computers can't do Have no imagination or creativity Have no intuition Have no sense of irony, subtlety, proportion, decorum, or humor Are not vindictive or cruel Are not purposeful Have no free will Do not get mad even if one asks the same thing over and over, Acknowledgement: Lawrence Snyder, “fluency with information technology” How Important is Clock Speed? Modern computers try to start an instruction on each clock tick Pass off finishing instruction to other circuitry Five instructions can be in process at the same time Does a 1 GHz clock really execute a billion instructions per second? Not a precise measurement. Computer may not be able to start an instruction on each tick, but may sometimes be able to start more than one instruction at a time Multi-core The use of multiple CPUs in the same computer Dual-core, Quad-core, multi-core Benefits: Challenges: Memory & Storage Memory and Storage Memory Hierarchical structure CPU <-> Cache <--> Ram <--> virtual memory/hard-disk Hardware communication: buses (33 to 1333 MHz) (66 MHz) (33 to 1333 MHz) ISA devices ISA bus (8.3 MHz) CPU (33 or 66 MHz) (up to 300 MHz) Cache Backside bus (speed of processor) RAM RAM: Random access memory (RAM) is the best known form of computer memory. RAM is considered "random access" because you can access any memory cell directly if you know the row and column that intersect at that cell Capacitors Word: cells of memory (one byte or multiple bytes) Address (grid structure) Types SRAM: Static random access memory DRAM: Dynamic random access memory Storage Hard drive CD or DVD Floppy disk USB key Tape Hard Drive (Magnetic disk) Capacity Speed, RPM (revolutions per minute) Format a disk Defragmentation Hard disk failure? RAID Redundant Array of Inexpensive (Independent) Disks A technology that simultaneous uses two or hard disks for better performance, reliability, and/or volume Seen as one disk Popular options: RAID 0, RAID 1, RAID 5 RAID 0 RAID 1 Acknowledgement: pictures taken from wikipedia RAID5 Acknowledgement: picture taken from wikepedia Solid State Drive Data storage device Pros: No moving part Faster access time Cons: Currently more expensive Optical disks CD-ROM (Compact disc) CD-W CD-RW DVD (digital video/versatile disk) Double layer, double sided DVD-RW BluRay and HD-DVD Q: is permanent storage “permanent”? Other Components Communicating with a computer Screen Keyboard Mouse Input Devices Keyboard Mouse Scanner Camera Gamepad Haptic device Gesture Keyboard Press a key Detect Interrupt Read Optical Mouse LED lights up Camera DSP Pass the information Position mouse on the screen Touch Screen http://electronics.howstuffwor ks.com/iphone1.htm http://electronics.howstuffworks.com/iphon e3.htm Output components Monitor Printer Dot-matrix Ink-jet Laser Dye sublimation Speaker Haptic device Interfaces USB (Universal Serial Bus) USB 1.0 (12Mbps), 2.0 (480Mbps), 3.0 (4.8Gb/s) Good interface, hot-swapping Firewire (IEEE 1394) SCSI (small computer system interface) IDE (Integrated Device Electronics) and EIDE (Enhanced IDE) USB USB 1.x/2.0 standard pinning Pin Name Cable color Description 1 VBUS Red +5 V 2 D− White Data − 3 D+ Green Data + 4 GND Black Ground Firewire SCSI Serial ATA (Advanced Technology Attachment) First generation (1.5 Gbit/s) SATA ports on a motherboard An Ipad(1) breakdown Touchscreen ~$95 A4 processor ~$28 16G memory ~$28 Rear case ~$10.50 WiFi/bluetooth chip ~$10.50 Total material costs: ~$260 Computer Layers Hardware BIOS Operating System Applications BIOS: Basic Input/Output Service BIOS refers to the firmware code usually stored on a flash memory chip on the motherboard that is run by a computer when first powered on. The chip holds a few small programs and some settings. BIOS performs two major tasks: -The Power On Self Tests (POST) are conducted. These tests verify that the hardware system is operating correctly. - The BIOS initiate the boot process. The BIOS looks for boot information that is contained in file called the master boot record (MBR) at the first sector on the disk (boot sector). Once an acceptable boot record is found the operating system is loaded which takes over control of the computer. OLPC Operating system: linux Chip: AMD 433MHz 1G Flash drive, no hard disk, no CD/DVD drive, Mesh networking, dual antenna Static version of WIki included, E-book an important functionality